Connecting devices of this kind are used in particular for making electrical connections between a current source and a gas collision protection device such as an air bag restraint arranged in the steering wheel dish or steering wheel switches of motor vehicles. Here, a wire arranged between the stator portion and the rotor portion which is rotatable relative thereto has a length such that it can follow the steering deflection, which is about three turns in both directions, wherein during steering wheel deflection the flexible wire expands outwards from a central position in one direction until it abuts against the stator portion and contracts inwards in the other direction until it abuts against the rotor portion. Furthermore it is known that the wire can be assigned positive restraint which is applied to the wire circumferentially and, on rotational movement of the rotor portion, causes predefined winding and unwinding of the wire.
EP 0 556 779 B2 discloses an electrical connecting device having an inner housing and an outer housing which consist of two relatively rotatable components. The connecting device has a flexible and spirally wound transmission medium which is accommodated in a chamber formed by the two housing portions. The transmission medium includes inner and outer ends which are attached to the inner and outer housings respectively, and inner and outer end sections which extend in opposite directions to each other round the circumference of the inner and outer housings, so that between the inner and outer end sections is formed a cable movement-reversing section in which the direction of movement of the transmission medium is reversed. In the chamber formed by the inner and outer housings there are a plurality of flexible cables including at least one transmission cable which serves as a transmission medium and at least one non-transmission dummy cable. Each of the cables has its own inner and outer ends which are attached to the inner and outer housings respectively. The inner and outer end sections of the cables extend in opposite directions to each other round the circumference of the inner and outer housings, so that between the inner and outer end sections are formed cable movement-reversing sections spaced apart at intervals from each other. Furthermore, the inner and outer end sections of the cables are fixed at a distance from each other.